Impact of an Oral Antineoplastic Renewal Clinic on Medication Possession Ratio and Cost-Savings
Purpose: The primary objective of this study was to evaluate the impact of a pharmacis t-driven oral antineoplastic (OAN) renewal clinic on medication adherence and cost savings.
Methods: This was a preimplementation and postimplementation retrospective cohort evaluation within a single US Department of Veterans Affairs health care system following implementation of a pharmacist-managed OAN refill clinic. The primary outcome was medication adherence defined as the median medication possession ratio (MPR) before and after implementation of the clinic. Secondary outcomes included the proportion of patients who were adherent from pre- to postimplementation and estimated cost-savings of this clinic. Patients were eligible for inclusion if they had received at least 2 prescriptions of the most commonly prescribed oral antineoplastic agents at the institution between September 1, 2013 and January 31, 2015.
Results: Of preimplementation patients, 96 of 99 (96.9%) were male and all patients (n = 35) in the postimplementation group were male. The mean age of the preimplementation group was 69.2 years while the postimplementation group was 68.4 years. Median MPR in the preimplementation group was 0.94, compared with 1.06 in the postimplementation group ( P < .001). Thirty-six (36.7%) patients in the preimplementation group were considered nonadherent to their OAN regimen compared with zero patients in the postimplementation group. Estimated total cost savings was $36,335 in the postimplementation period.
Conclusions: Implementation of a pharmacist-driven OAN renewal clinic was associated with a 12% increase in median MPR while saving an estimated $36,335 during the 5-month postimplementation period.
Limitations
Due to this study’s retrospective design, an inherent limitation is dependence on prescriber and refill records for documentation of initiation and discontinuation dates. Therefore, only the association of impact of pharmacist intervention on medication adherence can be determined as opposed to causation. We did not take into account discrepancies in day supply secondary to ‘held’ therapies, dose reductions, or doses supplied during an inpatient admission, which may alter estimates of MPR and cost-savings data. Patients in the postimplementation group intentionally received a 5 to 7-day supply buffer to account for potential prescription delivery delays due to holidays and inclement weather. This would indicate that the patients in the postimplementation group would have 15% oversupply due to the 5-day supply buffer, thereby skewing MPR values. This study did not account for cost avoidance resulting from early identification and management of toxicity. Finally, the postimplementation data only spans 4 months and a longer duration of time is needed to more accurately determine sustainability of renewal clinic interventions and provide comprehensive evaluation of cost-avoidance.
Conclusion
Implementation of an OAN renewal clinic was associated with an increase in MPR, improved proportion of patients considered adherent, and an estimated $36,335 cost-savings. However, prospective evaluation and a longer study duration are needed to determine causality of improved adherence and cost-savings associated with a pharmacist-driven OAN renewal clinic.